Exposure to audio signals at greater and greater amplitudes through the use of headphones and media devices, such as cell phones and MP3 players, has been increasing at an alarming rate. Exposure to audio signals at high decibel levels has been determined to be one of the primary causes of temporary and permanent hearing impairment, sometimes called noise-induced hearing loss. However, hearing impairment is not only increasing in the general population, but is increasing at a significantly faster rate among young people, especially in among those who utilize media devices and wear headphones (or wireless earpieces) for significant amounts of time.
The extent of hearing damage sustained through exposure to sounds has been determined to be a function of both the amplitude and the duration of the audio signals, and particularly exposure to audio signals at amplitudes that exceed a safe acoustic threshold. Permanent hearing damage is a cumulative effect of exceeding the minimum thresholds or safe pressure levels for extended periods. Various administrative bodies (such as the Occupational Safety and Health Administration (OSHA)) and health awareness agencies (such as the National Institute for Occupational Safety and Health (NIOSH)) have adopted guidelines for safe acoustic levels and listening durations